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    <p>If you're talking about causing a new method to be called before/after a function body, without changing the function body, you can base it on <a href="http://www.boost.org/doc/libs/release/libs/smart_ptr/sp_techniques.html#wrapper" rel="nofollow">this</a>, which uses a custom <code>shared_ptr</code> deleter to trigger the after-body function. It cannot be used for <code>try/catch</code>, since the before and after need to be separate functions using this technique.</p> <p>Also, the version below uses <code>shared_ptr</code>, but with C++11 you should be able to use <code>unique_ptr</code> to get the same effect without the cost of creating and destroying a shared pointer every time you use it.</p> <pre><code>#include &lt;iostream&gt; #include &lt;boost/chrono/chrono.hpp&gt; #include &lt;boost/chrono/system_clocks.hpp&gt; #include &lt;boost/shared_ptr.hpp&gt; template &lt;typename T, typename Derived&gt; class base_wrapper { protected: typedef T wrapped_type; Derived* self() { return static_cast&lt;Derived*&gt;(this); } wrapped_type* p; struct suffix_wrapper { Derived* d; suffix_wrapper(Derived* d): d(d) {}; void operator()(wrapped_type* p) { d-&gt;suffix(p); } }; public: explicit base_wrapper(wrapped_type* p) : p(p) {}; void prefix(wrapped_type* p) { // Default does nothing }; void suffix(wrapped_type* p) { // Default does nothing } boost::shared_ptr&lt;wrapped_type&gt; operator-&gt;() { self()-&gt;prefix(p); return boost::shared_ptr&lt;wrapped_type&gt;(p,suffix_wrapper(self())); } }; template&lt;typename T&gt; class timing_wrapper : public base_wrapper&lt; T, timing_wrapper&lt;T&gt; &gt; { typedef base_wrapper&lt; T, timing_wrapper&lt;T&gt; &gt; base; typedef boost::chrono::time_point&lt;boost::chrono::system_clock, boost::chrono::duration&lt;double&gt; &gt; time_point; time_point begin; public: timing_wrapper(T* p): base(p) {} void prefix(T* p) { begin = boost::chrono::system_clock::now(); } void suffix(T* p) { time_point end = boost::chrono::system_clock::now(); std::cout &lt;&lt; "Time: " &lt;&lt; (end-begin).count() &lt;&lt; std::endl; } }; template &lt;typename T&gt; class logging_wrapper : public base_wrapper&lt; T, logging_wrapper&lt;T&gt; &gt; { typedef base_wrapper&lt; T, logging_wrapper&lt;T&gt; &gt; base; public: logging_wrapper(T* p): base(p) {} void prefix(T* p) { std::cout &lt;&lt; "entering" &lt;&lt; std::endl; } void suffix(T* p) { std::cout &lt;&lt; "exiting" &lt;&lt; std::endl; } }; template &lt;template &lt;typename&gt; class wrapper, typename T&gt; wrapper&lt;T&gt; make_wrapper(T* p) { return wrapper&lt;T&gt;(p); } class X { public: void f() const { sleep(1); } void g() const { std::cout &lt;&lt; __PRETTY_FUNCTION__ &lt;&lt; std::endl; } }; int main () { X x1; make_wrapper&lt;timing_wrapper&gt;(&amp;x1)-&gt;f(); make_wrapper&lt;logging_wrapper&gt;(&amp;x1)-&gt;g(); return 0; } </code></pre>
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    1. COThat looks very interesting. Especially the link to Bjarne's paper.
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